Tuesday, June 1, 2021

Game 261: Space Shuttle: A Journey into Space

Photo by AtariAge.

I've been dreading this game. I find space physics fascinating, but my grasp on how masses transition from falling downward towards the earth to falling sideways around it is shaky at best. The prospect of having to learn actual orbital mechanics to play a game, made with NASA's consultation no less, has been bit intimidating.

I've also been quite intrigued, in a way that I wouldn't have been if this were a 48KB computer game. We've seen a simplistic and yet barely playable flight simulator crammed into 16KB on the Apple II. Space flight is inordinately more complicated, and Activision did this with half the program size, and only 128 bytes of RAM! And how are all those shuttle controls condensed into a one-button joystick plus the half-dozen console switches? How is any of this possible?

The short, incomplete answer is that there isn't that much simulation. It's mostly just following instructions - and with a manual 32 pages thick, there's no shortage of those - and errors result in fuel loss or mission aborting depending on severity. It isn't possible, for instance, to launch your rocket into the ground. It's still a very impressive technical achievement given the system's limitations, but I don't think I learned much about how spaceflight works by playing it.

There are six phases to the shuttle mission, and controls vary for each:

  • Launch
  • Stabilize orbit
  • Dock with the satellite
  • De-orbit
  • Re-entry
  • Final approach and landing
 

There are three game modes of incrementing difficulty:

  • Autosimulator - A demo mode where you don't need to touch any controls and can just watch the computer play the game for you. Partial manual controls override is possible in certain phases, but failure is impossible as far as I can tell.
  • Simulator - You have full control, but unlimited fuel. Fault tolerance is moderate - certain screwups will abort the mission, but others will just alert you to the problem and let you carry on in spite of it.
  • STS 101 - Full control, limited fuel, and all abort conditions are in effect. On a successful landing you are ranked based on how well you performed in the docking phase and how much fuel remains.


After spending a few hours coming to grips with everything, which included reading and re-reading the manual, and trying all of the modes in order with the manual in hand, I decided to do a "for real" run where I'd pursue the Mission Specialist rank, which requires docking with the satellite twice before de-orbiting, and landing safely with 3500 fuel units remaining.

 

Here's a rundown of the phases.

Prelaunch

Before launching the shuttle, you must make sure that the primary and backup engines are shut down, that the cargo doors are closed, and the landing gear up. These are done by flipping the console deck switches, which normally control color and difficulty in other games. In MAME, these are mapped to DIP switches.

Launch

Activate the countdown with the console reset switch.

At MET-15 (aka T minus 15), turn the primary engines on.

At MET-4, the gauge labeled 'C' will start to move.

 

When it does, you need to activate your thrusters to match by using the joystick button.

At MET-0, the restraining bolts are released and you have liftoff.


You'll have two new challenges in addition to needing to continually adjust your thrusters - you have to keep the shuttle centered with the joystick's horizontal motion, and keep it on the correct trajectory with the vertical motion. The console aids this, but good luck reading it during the first 26 miles.


At the second stage, the primary fuel tank detaches and things get a bit easier. The shuttle's altitude rises automatically, and its horizontal position is confusingly controlled by pushing up or down on the joystick. You really just want to keep the dot on the line by pushing down to move it to the right as it rises, and sometimes pushing up to correct oversteer. You'll still need to keep adjusting the shuttle's thrust and centering. Errors will sound a warning horn but generally only cost you fuel.

At 205 miles, you shut off the engines. You have a good amount of leeway, but the more off you are, the more effort (and fuel) you'll need to burn to adjust.

Stabilizing orbit


Once your engines are off, the console switches to a sine-wave showing your orbit and your position along with the satellite's. Stabilizing is straightforward if you can follow directions.
  • Turn the engines back on.
  • Pitch forward to -28°.
  • Turn the engines off.
  • Open the cargo bay doors.
 

The game isn't really simulating orbital mechanics here. Once you reach an altitude, you're in the satellite's orbit. There's a simple correlation between pitch and altitude drift, with -28° granting stability, and you need the engines on to change your pitch.

The cargo bay doors need to be open to cool the shuttle. Is that how it actually works in real life? What happens to the cargo when you open them in space?

Docking

 

As I said earlier, this is the most difficult and involving part of the game. You are now chasing a satellite in a stable orbit, and to dock, you've got to approach, get very close, match its velocity, altitude, and latitude, and hold steady for two seconds. To attain the rank of commander, you've got to do this six times before landing, and it gets more difficult each time, as the shuttle drifts and the satellite jitters, getting worse with each success.

The simplest method is by using the RCS engine clusters, available when the main engines are shut off, and this is more than good enough to dock with the satellite twice. With them, you may directly adjust the shuttle's orbital vector relative to the satellite, and as long as you don't do anything outrageous, the orbit will remain stable. Turning the engines on activates OMS in which the joystick button fires the powerful rear thruster, making longer distance maneuvers more fuel-efficient. You rely on pitch and yaw for direction, but making fine adjustments is difficult and accidentally destabilizing your orbit is easy.

With the RCS engines, altitude is adjusted by holding the joystick button and repeatedly tapping up or down. As you do this, the console displays your Z-axis delta, and the goal is to reach zero. Left and right adjust the Y-axis offset. Up/down without the button held changes your velocity and shows the X-axis offset (i.e. your distance to the satellite), but does not show your velocity, which you need to keep at exactly 23.9 once dX is 0 to match the satellite. The "game select" switch cycles through the console readouts, including velocity. You'll need to periodically check all three vectors, as the shuttle drifts and the satellite can become jumpy.

The fact that the console only shows one readout at a time is pretty annoying, and makes this phase fiddlier than it needs to be. You've got to keep checking your Z and Y deltas for drift, and the quickest way to do that is by moving on those axes, which changes them and wastes fuel. I wish you could view all three vector offsets, orbital velocity, and remaining fuel simultaneously, but you've got to keep cycling through them to check. Later computer versions would replace the now-unused thrust gauges with readouts for velocity and altitude, which isn't ideal but it's better than the original approach.

De-orbit burning

Unlike other phases, the game doesn't automatically "advance" to the de-orbit burn upon completion of the previous. It's a procedure you execute when you're ready for re-entry - ideally done after docking with the satellite enough times for your desired rank, but before fuel gets too low.

  • Wait until the satellite's distance increases to 128.
  • Correct Z-axis offset to 0.
  • Set speed to 23.9.
  • Activate primary engines.
  • Yaw to -128. This makes your shuttle face backwards as it travels in orbit tail-first.
  • Pitch to -4°
  • Ignite engines until your speed reduces to 19.0.
  • Yaw back to 0, so that the shuttle faces forward again.
  

The first three steps have nothing to do with realism; the game simply doesn't let you de-orbit while close to the satellite. After that, reversing the shuttle's yaw allows thrust to decelerate, and the proper pitch ensures that it does not climb or lose altitude.

I am honestly not sure if this step accomplishes anything apart from slowing down and putting distance between yourself and the satellite.

Reentry

After completing the above steps, there are two more steps to complete before beginning descent, which ensure the shuttle does not burn up on re-entry.

  • Pitch to 28°
  • Close the cargo bay doors.
 

Soon you'll rapidly lose altitude, and the trajectory console will show your descent course.


Controls are similar to the launch phase, but without the need to touch your thrusters. During the T-stage of reentry, extreme heat will disrupt your vision and instruments, leaving you flying blind for a few seconds.

Final approach


The last phase is landing the shuttle, and it's much easier than landing in Flight Simulator. All you have to do is keep the runway centered on the screen, and adjust the shuttle's pitch to keep its landing trajectory in the safe range indicated by the console. The readout shows your distance to the runway, and once it reaches zero, you may deploy the landing gear, and then simply push the nose down all the way to land.

On mode 3, you receive a rank.

 

As I had docked with the satellite twice and landed with just under 4500 fuel, I attained the rank of mission specialist, as planned. The next rank, pilot, would require docking four times and landing with more fuel than I managed with just two docks. I'm not really sure how you're supposed to do that, let alone attain "commander" rank by docking six times and landing with 7500 fuel, but I'm not interested enough to spend more time trying to find out.

GAB rating: N/A. Space Shuttle wasn't exactly a thrill-a-minute or even entertaining in the conventional sense, but that was never the point. I will reiterate that, despite what multiple retrospective reviews have said (often without making a real effort to attain competency), it isn't exactly a hardcore simulator nor is it immensely technical, and is more about partially replicating procedures than accurately modeling spaceflight. It's a niche product for sure, and I'm not sure it holds any appeal today beyond showing off what Activision's developers could pull off on the primitive Atari 2600 hardware, but I don't think it makes sense to rate it on a conventional good-bad scale.

7 comments:

  1. Douglas Adams wrote: "There is an art to flying, or rather a knack. The knack lies in learning how to throw yourself at the ground and miss."

    That's basically how you orbit. When you slow down, you change how far you are traveling laterally so that you stop missing the ground.

    The game "Kerbal Space Program" explains it really well.

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  2. It is one of those games where I want to say "Thank you for testing it, so I won't ever have to" :)

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  3. They did indeed open up the cargo bay doors to cool off the Space Shuttles. All cargo was strapped down and meant for space anyhow; perishables and the like were kept in the inhabited parts of the shuttle, not the bay (or were vacuum sealed and fine to be exposed to space anyhow).

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    Replies
    1. I learned this about the shuttle from a book during my "Kid who's really into space" phase years ago and it still annoys me when they get it wrong in shows. That and how they always depict the shuttle orbiting "sunny side up" (the shuttle orbits with its underside pointed away from the earth so that the heat shield will be pointed at the sun)

      Far as I can remember, the only major mainstream mass media depiction to get it right is, of all things "The West Wing". A subplot in the season 1 finale is that the White House is monitoring a crisis with the shuttle where they had to delay their landing because of an engine problem, but the cargo bay doors had jammed so they had to land before they overheated.

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    2. "the shuttle orbits with its underside pointed away from the earth so that the heat shield will be pointed at the sun"

      Does that mean that when looking out the flight deck window in orbit, you should be seeing the earth "above?"

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    3. Yep. There's a few movies that get it half-right by showing interior shots where people see the earth through the windows (Which you can't do if the shuttle's underside is facing the earth because of where the windows are located - the shuttle has to be landed by instruments only), but then shows the shuttle "right side up" with the Earth below it in long shots.

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  4. Wow, that's pretty hardcore to play a game through like this. I remember reading about this game and wanting it, but knowing how crap the Atari was and thinking it couldn't be any good. Intellivision could have given this a good home.

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